Heat treatment apparatus



Jan 28,1958 v. UPSHAW 2,821,650

HEAT TREATMENT APPARATUS Filed Feb. 14, 1955 WITNESSES INVENTOR AITTORNEY United States Patent HEAT TREATMENT APPARATUS Vert Upshaw, Elmira, N. Y., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application February 14, 1955, Serial No. 487,886

Claims. (Cl. 315-57) This invention relates to the heat treatment of devices and more particularly to apparatus for the heat treatment of portions of electron discharge devices.

It is an object of this invention to provide improved apparatus for heat treating portions of an electron discharge device.

It is another object of this invention to provide improved apparatus for heat treating relatively inaccessible portions of electron discharge devices.

It is a further object to provide improved means for heat treating relatively inaccessible portions of electron discharge devices by induced currents.

It is an additional object to provide an improved method of heat treating portions of an electron discharge device.

It is a difierent object to provide improved means for removing undesired heat from certain portions of an electron discharge device.

These and other objects of the invention will be apparent from the following description taken in accordance with the accompanying drawings which form a part of this application and in which:

Figure l is a partial cross-sectional view of an electron discharge device of a type to which my invention may be suitably applied embodying one form of my invention;

Fig. 2 is a perspective view of the apparatus in accordance with this invention;

Fig. 3 is a perspective view of another form of the ap' paratus in accordance with this invention; and

Fig. 4 is a perspective view of still another form of the apparatus in accordance with this invention.

In Fig. 1 there is shown an electron discharge device of the type of disk seal tube known as a lighthouse tube including an anode connection 11, an anode 13, a cathode 15 and a control grid 17 positioned between the anode 13 and the cathode 15. A heater 19 is enclosed within the cathode 15. A base member 21 supports the electron discharge device. The elements of the electron discharge device are enclosed within a suitable glass or metal envelope 23. A current inducing member 25 which may be a radio-frequency coil is positioned outside the electron discharge device. A continuous circuit member 27 is positioned inside the envelope 23 of the electron discharge device so that a current may be induced into a first portion 29 of the continuous circuit member 27 from the current inducing member 25. A second portion 31 of the continuous circuit member 27 is positioned so that a current may be induced from the second portion 31 into the desired electrically conductive member, in this case a part of the anode 13.

In Fig. 2, there is shown a continuous circuit member 27 having a first portion 29 and a second portion 31. In Fig. 3, there is shown another form of a continuous circuit member 33 having a first portion 35 and a second portion 37. In Fig. 4, there is shown still another form of a continuous circuit member 39 having a first portion 41 and a second portion 43.

2,821,660 Patented Jan. 28, 1958 "ice These continuous circuit members 27, 33, and 39 should be made of a material that has a low resistivity, low vapor pressure and should be stable over a wide range of temperatures. Preferably, the material should not be easily oxidized but if it is oxidizable the oxide should have a high adherence. In some applications good thermal radiation is desirable. A preferred material for this use is copper. Some copper alloys, such as Monel would be acceptable and certain steels, such as stainless steel, would be preferred in some usages.

In accordance with my invention, when a current is induced from the current inducing member 25 into the first portion 29 of the continuous circuit member 27, the current will be conducted through the circuit member 27 and induced into the electrically conductive member 13 by the second portion 31. The current induced into the electrically conductive member 13 will heat it as may be desired during the manufacture of the electron discharge device, particularly during the exhaust cycle. By sufiicient heat treatment during the exhaust cycle, gas will be removed from the heated part, and therefore, the subsequent undesired evolution of gas during operation is markedly reduced. Any evolution of gas during the normal operation of an electron discharge device is very harmful to the device and will considerably reduce the useful life of the device.

Although there are a considerable number of methods for heat treating parts of tubes, many attractive designs have had limited practicability because of the necessity of degassing inaccessible internal parts. My invention allows these inaccessible internal parts to be heated so that they are degassed. As the circuit member 27 may be of any desired shape and size, heat may be induced into parts of an electron discharge device that could not be heated by prior methods. For example if a part to be heated were very close to a sealed area or if it were masked by another part, it was not previously practical to adequately degas that particular part.

Another advantage of my invention is the additional cooling during the normal operation of the part previously degassed. The circuit member 27 will conduct heat away from the hot area and, in turn, will act as an efficient heat transfer member because of its additional surface area.

While the present invention has been shown in a few preferred forms only, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof. It is also understood that the application of this invention is not limited to electron discharge devices.

I claim as my invention:

1. In an electron discharge device having an envelope and an electrically conductive member, the combination of a primary current inducing member, a continuous circuit member having a first portion positioned relative to said current inducing member so that a current may be induced into said first portion from said current inducing member, said continuous circuit member having a second portion positioned relative to said electrically conductive member so that currents are induced into said electrically conductive member when current flows through said second portion of said continuous circuit member.

2. In an electron discharge device having an envelope and an electrically conductive member, the combination of a primary current inducing member, a continuous circuit member having a first portion positioned relative to said current inducing member so that a current may be induced into said first portion from said current inducing member, said continuous circuit member having a second portion positioned relative to said electrically conductive member so that currents are induced into said electrically "conductive member from said second portion when current flows throughsaid second portionofsaid continuous circuit member, said primary current inducing member being positioned externally with respect to the envelope or the electron discharge device.

3. In apparatus 'for the "heat treatment of a predeter- "mined 'portion of an electron discharge device, said device including an electrically conductive member, the combination of a primary current inducing-member, a continuous circuit member having "a first-portion positioned relative to saidcurrent inducing member so that a current may be induced into saidfirsfportion from said current inducing member, said continuous circuit member having a second portion positioned relative to 'said elec- *trica'lly conductive member so thata 'currentisinduced into said electrically conductive'mernber from-said second portion when current flows through said second portion of said continuous circuitmember.

4. 'ln apparatus for the heat treatment of a predetermember so that :a current isinduced into "said electrically conductive member from said second portion'when current flows through said second portion of said continuous circuit-member, said discharge device having an envelope, and further characterized by said primary current inducing member being positioned externally with respect to the envelope of the electron discharge device.

5. A method of heat treating a predetermined portion of an electron discharge :device, said method including the steps of positioning a continuous circuit member so that a first portion of said continuous circuit member is ,positionedtrelative toaprimary current inducing member in such a way thata current may be induced into said first portion from said primary current inducing member, and positioning a second portion of said continuous circuit member relative to said predetermined portion that is to be heat treated '80 that a current may be induced into said predetermined portion from said second portion when current flows through said second portion of said continuous circuit member, inducing a current into said first portion of said continuous circuit member from said primary current=inducingmember, and inducing a current from said second portion :ofsaid continuous cireuit member into'said predetermined portion as desired.

References Cited in the file of this .patent UNITED STATES PATENTS Re. 21,326 Rava Jan. 1 6, 1940 890,73d "Troy June 16, 1908 1,738,399] etal Dec. -10, 1929 

